package com.feeyo.audio.codec;

/**
 * PCMU  -  PCM u-law audio 
 * PCMA  -  PCM a-law audio
 *
 */
public class PcmuDecoder extends Decoder { 
	
  private static short muLawDecompressTable[] = new short[]{ 
      -32124, -31100, -30076, -29052, -28028, -27004, -25980, -24956, 
      -23932, -22908, -21884, -20860, -19836, -18812, -17788, -16764, 
      -15996, -15484, -14972, -14460, -13948, -13436, -12924, -12412, 
      -11900, -11388, -10876, -10364, -9852, -9340, -8828, -8316, 
      -7932, -7676, -7420, -7164, -6908, -6652, -6396, -6140, 
      -5884, -5628, -5372, -5116, -4860, -4604, -4348, -4092, 
      -3900, -3772, -3644, -3516, -3388, -3260, -3132, -3004, 
      -2876, -2748, -2620, -2492, -2364, -2236, -2108, -1980, 
      -1884, -1820, -1756, -1692, -1628, -1564, -1500, -1436, 
      -1372, -1308, -1244, -1180, -1116, -1052, -988, -924, 
      -876, -844, -812, -780, -748, -716, -684, -652, 
      -620, -588, -556, -524, -492, -460, -428, -396, 
      -372, -356, -340, -324, -308, -292, -276, -260, 
      -244, -228, -212, -196, -180, -164, -148, -132, 
      -120, -112, -104, -96, -88, -80, -72, -64, 
      -56, -48, -40, -32, -24, -16, -8, 0, 
      32124, 31100, 30076, 29052, 28028, 27004, 25980, 24956, 
      23932, 22908, 21884, 20860, 19836, 18812, 17788, 16764, 
      15996, 15484, 14972, 14460, 13948, 13436, 12924, 12412, 
      11900, 11388, 10876, 10364, 9852, 9340, 8828, 8316, 
      7932, 7676, 7420, 7164, 6908, 6652, 6396, 6140, 
      5884, 5628, 5372, 5116, 4860, 4604, 4348, 4092, 
      3900, 3772, 3644, 3516, 3388, 3260, 3132, 3004, 
      2876, 2748, 2620, 2492, 2364, 2236, 2108, 1980, 
      1884, 1820, 1756, 1692, 1628, 1564, 1500, 1436, 
      1372, 1308, 1244, 1180, 1116, 1052, 988, 924, 
      876, 844, 812, 780, 748, 716, 684, 652, 
      620, 588, 556, 524, 492, 460, 428, 396, 
      372, 356, 340, 324, 308, 292, 276, 260, 
      244, 228, 212, 196, 180, 164, 148, 132, 
      120, 112, 104, 96, 88, 80, 72, 64, 
      56, 48, 40, 32, 24, 16, 8, 0 
  }; 

  @Override 
  public byte[] process(byte[] media) { 
      byte[] res = new byte[media.length * 2]; 
      int j = 0; 
      for (int i = 0; i < media.length; i++) { 
          short s = muLawDecompressTable[media[i] & 0xff]; 
          res[j++] = (byte) s; 
          res[j++] = (byte) (s >> 8); 
      } 
      return res; 
  }
}